Functions outside of classes:get_interfaces(only_up=False): returns a list of all NetInterface.
If only_up, will only return the ones currently marked UP.get_wireless_interfaces(): returns a list of wireless NetInterface.get_accesspoints(): returns a list of visible AccessPoints.ifdown_all(): take all interfaces down, killing any wpa_supplicant or dhcpkill_by_name(namelist): Kill a any running processes that include any
of the names in namelist. Return a list of actual process names killed.

Returns a list of NetInterfaces for all eth*, wlan* or mlan*
interfaces visible from ifconfig.
Omit lo, vpn, ipv6 and other non-physical interfaces.
If only_up is true, use ifconfig instead if ifconfig -a.